\textit{Panel A: Machine horsepower  } &   \multicolumn{2}{c}{Not invested} & \multicolumn{2}{c}{Invested} \\    
                    &\multicolumn{1}{c}{Est.}&\multicolumn{1}{c}{S.E.}&\multicolumn{1}{c}{Est.}&\multicolumn{1}{c}{S.E.}\\
 \hline &&&\\   
$1-\delta$          &       0.873&       0.061&       1.017&       0.005\\
 &&&&\\  R-squared  &   \multicolumn{2}{c}{.782} & \multicolumn{2}{c}{.974} \\  Observations &        \multicolumn{2}{c}{3558} &  \multicolumn{2}{c}{3279} \\ &&&&\\  
\hline \textit{Panel B: Equine horsepower  } &  \multicolumn{2}{c}{Not invested} & \multicolumn{2}{c}{Invested} \\    
                    &\multicolumn{1}{c}{Est.}&\multicolumn{1}{c}{S.E.}&\multicolumn{1}{c}{Est.}&\multicolumn{1}{c}{S.E.}\\
 \hline &&&\\   
$1-\delta$          &       0.849&       0.073&       0.993&       0.012\\
 &&&&\\  R-squared  &   \multicolumn{2}{c}{.721} & \multicolumn{2}{c}{.934} \\  Observations &        \multicolumn{2}{c}{3558} &  \multicolumn{2}{c}{3279} \\ &&&&\\  
 \hline &&&\\   
